Information storage medium containing interactive graphics stream for change of AV data reproducing state, and reproducing method and apparatus thereof

ABSTRACT

A method of reproducing interactive graphics data including menu data, the method including receiving a reproduction command of the interactive graphics data during reproduction of AV data, and changing a reproducing state of the AV data.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 10/923,017, filed Aug. 23, 2004 in the U.S. Patentand Trademark Office, which claims the priority of Korean PatentApplication No. 2004-8345, filed on Feb. 9, 2004, in the KoreanIntellectual Property Office, the disclosure of which is incorporatedherein in its entirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to reproducing audio/video (AV) data, and,more particularly, to an information storage medium containinginteractive graphics streams capable of changing the reproducing stateof AV data, and a reproducing method and apparatus that use theinteractive graphics streams capable of changing the reproducing stateof AV data.

2. Description of the Related Art

FIG. 1 is a diagram showing a variety of streams being multiplexed intoa main stream.

Referring to FIG. 1, a main stream 110 of multimedia pictures is formedby multiplexing a video stream 102, an audio stream 104, a presentationgraphics stream 106 to provide subtitles, and an interactive graphicsstream 108 to provide a menu containing buttons for interaction with auser. The interactive graphics stream 108 includes a plurality ofsegments.

FIG. 2 is a diagram showing the structure of a display set included inthe interactive graphics stream 108.

Referring to FIG. 2, the interactive graphics stream 108 is formed witha plurality of display sets, each of which includes a plurality ofsegments. Each of the segments forming the display set will now beexplained. An interactive composition segment (ICS) 210 defines displayinformation of an “interactive display” in the interactive graphicsstream 108. The “interactive display” is used to provide graphicselements such as a button corresponding to a command. A palettedefinition segment (PDS) 220 is used to define a palette which providesoutput colors or degrees of transparency that should be applied to pixelvalues in a graphics plane in relation to the interactive graphicsstream 108. There can be a plurality of object definition segments (ODS)230-1 through 230-n, which are actual graphics data in the interactivegraphics stream 108. An end segment 240 is used to indicate the end of adisplay set.

This interactive graphics stream 108 is reproduced together with an AVstream. When a menu is displayed on the screen, in order to navigate themenu while the AV stream is being reproduced, the reproduction of AVdata continues even during reproduction of the interactive graphicsstream corresponding to the menu. Accordingly, some scenes of a moviemay be missed during menu navigation, or if the menu box takes up alarge part of the screen, important scenes may be missed.

SUMMARY OF THE INVENTION

The present invention provides an information storage medium containingan interactive graphics stream capable of changing the reproducing stateof AV data when menu navigation is performed, and a reproducing methodand apparatus using the medium.

Additional aspects and/or advantages of the invention will be set forthin part in the description which follows and, in part, will be obviousfrom the description, or may be learned by practice of the invention.

According to an aspect of the present invention, there is provided aninformation storage medium including: AV data; presentation graphicsdata including subtitle information corresponding to the AV data; andinteractive graphics data including menu data, wherein the interactivegraphics data further includes a reproducing state change navigationcommand to change the reproducing state of the AV data and/or thepresentation graphics data.

The interactive graphics data may include at least one display setformed with a plurality of segments, the segments may include aninteractive composition segment including composition information of themenu data, and the interactive composition segment may include thereproducing state change navigation command. The reproducing statechange navigation command may be executed before the menu is displayed.

A user command corresponding to the interactive graphics data maycontrol the reproducing state of the AV data and/or the presentationgraphics data.

According to another aspect of the present invention, there is provideda method of reproducing interactive graphics data including menu data,the method comprising: receiving a reproduction command of theinteractive graphics data during reproduction of AV data; and changing areproducing state of the AV data.

A reproducing state change navigation command, which may be included inthe interactive graphics data, to change the reproducing state of the AVdata may be performed before changing the reproducing state of the AVdata. The reproducing state change navigation command may be a commandto change the reproducing state of the AV data to a “Still” state.

According to still another aspect of the present invention, there isprovided a reproducing apparatus comprising: an object buffer to receiveinteractive graphics data comprising menu data; and a graphicscontroller to control the reproducing state of the received interactivegraphics data, wherein the interactive graphics data includes areproducing state change navigation command to change the reproducingstate of the AV data and/or presentation graphics data.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages of the invention will becomeapparent and more readily appreciated from the following description ofthe embodiments, taken in conjunction with the accompanying drawings ofwhich:

FIG. 1 is a diagram showing a variety of streams being multiplexed intoa main stream;

FIG. 2 is a diagram showing the structure of a display set in aninteractive graphics stream;

FIG. 3 is a diagram showing the structure of an interactive compositionsegment (ICS) in an interactive graphics stream, which is designed toimplement a menu;

FIG. 4 is a diagram illustrating a valid display period of a pop-upmenu;

FIG. 5 is a diagram illustrating a valid display period of an always-onmenu;

FIG. 6 is a diagram showing states that an AV presentation can have whena presentation engine is active;

FIG. 7 is a diagram showing the structure of an ICS to which apre-command block is added, according to an embodiment of the presentinvention that implements a temporary stop function. The pre-commandblock is added when a pop-up menu is prepared so that the reproducingstate of AV data can be controlled;

FIG. 8 is a diagram showing the structure of an ICS to which a “Still”command is allocated in a menu screen, according to another embodimentof the present invention that implements a temporary stop function; and

FIG. 9 is a diagram showing a reproducing apparatus according to anembodiment of the present invention which reproduces an interactivegraphics stream.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the embodiments of the presentinvention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to the like elementsthroughout. The embodiments are described below to explain the presentinvention by referring to the figures.

Referring to FIG. 3, an interactive composition segment (ICS) includes aplurality of page structures. The ICS is designed to implement aplurality of menu pages, or other forms of a graphical user interface,within a valid display period of a display set to which the ICS belongs.A page is a group of buttons forming one menu, which is distinguishedfrom other pages by a page_id. That is, one ICS includes a plurality ofpages. Both a pop-up menu and an always-on menu have identical ICSstructures, and an attribute indicating that a menu implemented by theICS is a pop-up menu or an always-on menu is written in segmentdescription attributes.

FIG. 4 is a diagram illustrating a valid display period of a pop-upmenu.

The pop-up menu is not displayed on the screen even when the time pointat which AV data is reproduced reaches the presentation time stamp (PTS)of Epoch Start of ICS (start of new epoch of ICS), and the pop-up menuis only displayed on the screen when a button to which a user operationis allocated, such as “PopUp_on( )” for a user to select to display themenu, is selected. The term “epoch” will be explained later. The menudisappears in response to a user operation such as “PopUp_off( )” or ata time point of composition_time_out_pts of the ICS. The termcomposition_time_out_pts describes the end time of the interactivedisplay in an epoch. At the end time, the interactive display is nolonger valid and consequently shall no longer be displayed. Accordingly,the interval indicated by reference number 410, from the PTS time pointof the ICS to the time point of composition_time_out_pts, is the validdisplay period of the pop-up menu, and the time a menu screen isactually displayed on the screen, between PopUp_on( ) and PopUp_off( )within the valid display period, is an interactive display period.

Here, the interactive display period is a valid interval in which thepop-up menu can be displayed, that is, an interval where user operationsof PopUp_on( ) and PopUp_off( ) by the user can be applied. Theinteractive display period is an interval in which the menu is actuallydisplayed on the screen.

The interactive graphics data stream is formed with one or more units,each referred to as an epoch, considering the operation model of aninteractive graphics decoder. All interactive graphics objects in anepoch period are decoded and stored continuously in an object buffer inan interactive graphics decoder.

That is, in one epoch period, repeated use of decoded interactivegraphics objects is possible. Accordingly, unless the next epoch dataare input, the data are continuously maintained in the decoder, and atthe moment when the current epoch ends and the next epoch begins, allbuffers in the decoder are reset and all data stored in the objectbuffers disappears.

Each segment in one display set is written in a packetized elementarystream (PES), which is a packet unit of an MPEG-2 transport stream.Here, decoding of the display set is performed for a periodcorresponding to the decoding time stamp (DTS) time contained in the PESpacket, and output of the packets on the screen begins at the PTS time.The output completion time of the display set is determined by a valuein the composition_time_out_pts field recorded in the ICS.

FIG. 5 is a diagram illustrating a valid display period of an always-onmenu.

When the reproducing time point of AV data becomes the PTS of EpochStart of ICS, the first page of the always-on menu is displayed on thescreen, and at the time point of composition_time_out_pts of the ICS,the always-on menu disappears automatically. Accordingly, the intervalindicated by reference number 510, from the PTS time point of the ICSand to the time point of composition_time_out_pts, is the valid displayperiod of the always-on menu, and the valid display period is the sameas the interactive display period when the menu is actually displayed onthe screen.

As described above with reference to FIGS. 4 and 5, there is adifference between the pop-up menu and the always-on menu in that thepop-up menu is displayed on the screen within a valid display period inan epoch set by a user operation, while the always-on menu is displayedautomatically at the PTS time point of the ICS. Each of these menus isdisplayed together with reproduction of AV data. Usually, even when amenu is displayed, the reproduction of AV data continues. Accordingly, amenu box is displayed during reproduction of AV data, and if a userperforms menu navigation during reproduction of AV data, the scenescannot be viewed correctly because of the part hidden by the menu box,or movie scenes that are playing during the menu navigation can bemissed.

FIG. 6 is a diagram showing states that an AV presentation can have whena presentation engine is active.

Referring to FIG. 6, in AV presentation, there are states such as“Play”, “Trick Play”, and “Still”. “Play” indicates a state wherereproduction is performed at a normal speed, that is, ×1.0 (speedmultiplied by 1), and “Trick Play” indicates a state where reproductionis performed at a lower or higher speed than the ×1.0 speed. “Still”indicates that a last scene is continuously displayed on the screen andreproduction is performed at a speed of ×0. Accordingly, in the “Still”state, reproduction of video and audio data is temporarily stopped butthe navigation system operates continuously. The “Still” state isdifferent from a “Pause” state. In a “Pause” state, all operations,including the operations of the navigation system, stop.

Accordingly, in the present invention, a navigation command “Still”,enabling a user to change the state of AV presentation from “Play” to“Still”, is defined such that when a menu is displayed duringreproduction of AV data, the user does not miss movie scenes. That is,according to the intention of a content manufacturer, the “Still”navigation command is made to be used so that when a menu is reproduced,reproduction of AV data can be temporarily stopped.

FIG. 7 is a diagram showing the structure of an ICS to which apre-command block is added, according to an embodiment of the presentinvention which implements a temporary stop function. The pre-commandblock is added when a pop-up menu is prepared so that the reproducingstate of AV data can be controlled.

Referring to FIG. 7, it can be seen that a pre-command block is added toa page structure data area. The pre-command block contains navigationcommands that should be executed before the page structure datacontaining the pre-command block are displayed on the screen. If amanufacturer wants the reproduction of AV data to be continued when apop-up menu page defined by the ICS is executed by a user, themanufacturer can choose not to include a “Still” command in thepre-command block. Also, if the designer wants the reproduction of AVdata to stop temporarily, the manufacturer can include a “Still” commandin the pre-command block so that reproduction of AV data can betemporarily stopped before the menu page is displayed.

FIG. 8 is a diagram showing the structure of an ICS to which a “Still”command is allocated in a menu screen, according to another embodimentof the present invention that implements a temporary stop function.

Referring to FIG. 8, in this embodiment, a manufacturer can provide amenu screen to display on the screen in which a “Still” command isallocated to a predetermined button, such that according to userselection, the reproducing state of AV can be changed to a temporarystop state.

As described above, by using the “Still” navigation command changing thestate of AV presentation from “Play” to “Still”, when a pop-up menu oran always-on menu is executed, the reproducing state of AV data can becontrolled according to the intention of the manufacturer.

FIG. 9 is a diagram showing a reproducing apparatus according to anembodiment of the present invention that reproduces an interactivegraphics stream.

Referring to FIG. 9, a block diagram of an interactive graphics decoderof a reproducing apparatus according to an embodiment of the presentinvention is provided. In an MPEG-2 TS packet, which is a main streamread out from a storage medium, only an interactive graphics stream isselectively taken and transferred to a transport buffer 904, and thentransmitted to an interactive graphics decoder. In a coded data buffer906, data to be decoded is stored. In a stream graphics processor 908,the data is decoded and object data for button images is transmitted toan object buffer 910, and composition information is transmitted to acomposition buffer 912 such that screen output of the interactivegraphics stream is controlled.

Upon reaching the PTS time, corresponding to the start of screen outputof the interactive graphics stream, the composition buffer 912 controlsa graphics controller 914 such that images to be output on the currentscreen are determined and transmitted from the object buffer 910 to agraphics plane 916, and color information is transmitted to a colorlook-up table 918 to form an interactive graphics stream on the screen.Also, the graphics controller 914 receives an input from the user andchanges the button state in response to position movement of orselection of a button, and indicates the result on the screen output.

Meanwhile, the embodiments of the interactive graphics streamreproduction method described above can be written as a computerprogram. Codes and code segments forming the programs can be easilyinferred by a computer programmer in the field. The program may bestored in an information storage medium, and read and executed by acomputer such that the method is implemented. Examples of theinformation storage medium include magnetic storage media, opticalrecording media, and storage media such as carrier waves.

The embodiments presented in this description should be considered in adescriptive sense only, and not for purposes of limitation. Therefore,the scope of the invention is defined not by the detailed description ofthe invention but by the appended claims, and all differences within thescope will be construed as being included in the present invention.

According to the present invention as described above, the methodcapable of controlling the state of AV presentation, that is, the stateof a presentation engine, when a pop-up menu or an always-on menu isdisplayed, is provided. Accordingly, the present invention enables amanufacturer or a user to maintain or temporarily stop the reproductionof AV data when a menu is reproduced.

Although a few embodiments of the present invention have been shown anddescribed, it would be appreciated by those skilled in the art thatchanges may be made in these embodiments without departing from theprinciples and spirit of the invention, the scope of which is defined inthe claims and their equivalents.

What is claimed is:
 1. A method of reproducing interactive graphicsdata, the method comprising: reproducing audio video (AV) data;reproducing the interactive graphics data along with the AV data using afirst command, the interactive graphics data including an interactivecomposition segment to implement at least one pop-up menu page whichincludes at least one button containing at least one of navigationcommand; and changing a reproducing state of the AV data in response toa button corresponding to a predetermined navigation command beingselected from among the at least one of navigation command included inthe pop-up menu page, wherein the changed reproducing state of the AVdata comprises a still state in which a last scene of the video data iscontinuously displayed, a reproducing of the audio data associated withthe video data is temporarily stopped, and the navigation functionoperates continuously.
 2. The method of claim 1, wherein the commandincluded in the interactive graphics data is executed automatically uponthe reproducing of the interactive graphics data.
 3. The method of claim1, wherein the command included in the interactive graphics data isexecuted upon receipt of a command from a user.
 4. The method of claim1, wherein interactive graphics data includes an interactive compositionsegment to implement at least one pop-up menu page, and the at least onepop-up menu page covers the at least a portion of the reproduced AVdata.
 5. The method of claim 4, wherein the at least one pop-up menupage includes the command to change the reproducing state of the AVdata.
 6. The method of claim 5, wherein the command to change thereproducing state of the AV data is received via a button included inthe at least one pop-up menu page.
 7. The method of claim 1, wherein,during the still state the interactive graphics data is capable ofreceiving navigation commands from a user to change the reproducingstate of the video data.